A fluid dispense tip, also referred to as a “pin” or “needle,” is utilized in a variety of applications. For example, a fluid dispense tip, when attached to a fluid dispense pump system, is used to deposit a precise amount of fluid material, such as glue, resin, or paste, at precise positions on a semiconductor substrate. Examples of such fluid dispense pumps are described in U.S. Pat. No. 6,511,301, U.S. patent application Ser. No. 10/948,850, filed Sep. 23, 2004, entitled “Fluid Pump and Cartridge,” U.S. Pat. Nos. 6,892,959, 6,983,867, and U.S. patent application Ser. No. 10/810,236, filed Mar. 26, 2004, entitled “Dispense Pump with Heated Pump Housing and Heated Material Reservoir,” the contents of each being incorporated herein by reference in their entirety.
The increase in integration density in semiconductor devices has led to the need for dispense needles to deposit fluid materials onto a substrate with higher precision, requiring fluid materials to be deposited in the form of dots having small diameters or lines having narrow widths, or other dispense patterns.
Several approaches are used to form a dispense tip that can dispense fluid material patterns, such as dots or lines. In one conventional approach, a neck of a dispense tip is formed by rolling a flat portion of machined metal into a cylindrical form and sealing the edges of the rolled, machined metal.
In another conventional approach, similar to that disclosed in United States Patent Application Publication Serial No. 2003/0071149, the contents of which are incorporated by reference in their entirety, a dispense tip is formed by applying a conically-shaped mandrel against a malleable metallic disk and forcing the metal to be drawn down into a first cavity of a first die. The formed metal is removed from the first die. These steps are repeated using progressively smaller-diameter mandrels and progressively smaller-diameter circular dies until the finished dispense tip is formed.
In another approach, as disclosed in U.S. Pat. Nos. 6,547,167, 6,981,664, 6,957,783, the contents of which are incorporated herein by reference in their entirety, and as illustrated in FIG. 1, a body and a neck of a dispense tip are machined from a common stock, and a bore is drilled through the body and the neck, resulting in a bore in the neck having a relatively large constant first diameter that tapers down to an outlet having a relatively small second diameter.
In another approach, also disclosed in U.S. Pat. No. 6,547,167, the contents of which are incorporated herein by reference in their entirety, a dispense tip is molded or cast from materials such as plastics, composites, metals, or ceramics, other materials known to those of skill in the art as being used in the formation of a dispense tip.
As demands for dispensing precision continue to increase with the demand of further integration of devices, the above approaches have reached physical limits in their ability to provide dispense tips with outlets smaller than those achievable by the smallest available machining tools or die casts. This limits the ability to control dispensing operations of material at such fine dimensions and volumes.